Question 880578
M does ( 1 job ) / ( 4 hrs )
K does ( 1 job ) / ( 6 hrs )
L does ( 1 job ) / ( 8 hrs )
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Add their rates of working to
get their rate working together
{{{ 1/4 + 1/6 + 1/8 = 1/t }}}
Multiply both sides by {{{ 24t }}}
{{{ 6t + 4t + 3t = 24 }}}
{{{ 13t = 24 }}}
{{{ t = 24/13 }}}
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Together, they take {{{ 24/13 }}} hr
to do 1 job
{{{ (1/4)*( 24/13 ) = 6/13 }}}
For K:
{{{ (1/6)*( 24/13 ) = 4/13 }}}
For L:
{{{ (1/8)*( 24/13 ) = 3/13 }}}
M does 6/13 of the work
check:
{{{ 6/13 + 4/13 + 3/13 = 13/13 }}}
OK